1. Technical Field
The present disclosure relates to military aircraft.
2. Description of Related Art
Typically tactical aircraft are configured for the conditions that they are expected to encounter on particular missions. For example, an aircraft will be configured with a large fuel supply and only light (or no) armament for a mission that is expected to involve long-term surveillance with limited (or no) enemy engagements. Conversely, an aircraft will be configured with a small fuel supply and heavy armament, if the mission is expected to be of short duration with heavy enemy engagement. Configuring aircraft in accordance with their anticipated mission conditions allows efficient use to be made of the limited payload capacities of aircraft.
One method of configuring an aircraft is to add external fuel tanks to the aircraft. The additional fuel capacity enables the aircraft to fly missions of relatively long distance and/or duration. However, external fuel tanks create drag and may limit the aircraft's maneuverability. In fact, often so much drag is created that the range of the aircraft is increased only by about half of what it would have been increased had the extra fuel capacity been created within the aircraft.
In practice, the actual distances flown and weaponry required will vary greatly within a given mission as the operational tempo changes. Aircraft configured for specific missions at launch frequently find that they are ill suited for the conditions they actually encounter. While manned aircraft endurance can be extended nearly indefinitely through aerial refueling, there are no known systems by which aircraft can be rearmed in flight. Today, once an aircraft has spent its weapons magazine, it must return to base, regardless of fuel state.
Armed unmanned air vehicles (UAV's) and unmanned combat air vehicles (UCAV's) are particularly sensitive to these problems. These types of aircraft typically fly long missions where the operational tempo can change dramatically over the course of a given mission. For example, a UAV may have been outfitted for a low intensity conflict (more fuel, less weapons), but over the course of its 30+ hour mission new conflicts may have flared up. In such situations, the hunter-killer aircraft may have more targets than weapons, forcing the UCAV to return to base with targets not prosecuted, or forcing commanders to launch additional aircraft. Launching more aircraft requires the commitment of additional resources to the battle theatre (with the requisite support and supplies) just to satisfy the possible need for increased firepower.